Information Notice No. 91-24: Recent Operating Experience Involving Reactor Operation Without a Licensed Reactor Operator or Senior Reactor Operator Present in the Control Room

                                UNITED STATES
                           WASHINGTON, D.C.  20555

                               March 26, 1991

                                   REACTOR OPERATION WITHOUT A LICENSED 
                                   REACTOR OPERATOR OR SENIOR REACTOR 
                                   OPERATOR PRESENT IN THE CONTROL ROOM


All holders of operating licenses or construction permits for nuclear power, 
test, and research reactors, and all Part 55 licensed operators.


This information notice is provided to alert addressees to recent operating 
experience involving reactor operation without a licensed reactor operator 
or senior reactor operator present in the control room.  It is expected that 
recipients will review the information for applicability to their facilities 
and consider actions, as appropriate, to avoid similar problems.  However, 
suggestions contained in this information notice do not constitute NRC re-
quirements; therefore, no specific action or written response is required.

Description of Circumstances:

On January 22, 1991, the Pennsylvania State University (PSU) 1 MW TRIGA 
research reactor was operating at 1 MW (rated thermal power).  During this 
operational period, the reactor operator left the control room briefly to 
provide University personnel access to the reactor bay area through a locked 
door.  The reactor operator was the only person present in the control room 
and adjoining reactor bay area before the University personnel were 
admitted.  The reactor operator then returned to the control room once the 
University personnel were admitted.  No other operational occurrences were 
associated with the event.

On December 20, 1990, General Public Utilities (GPU), the licensee, was 
operating the Oyster Creek Nuclear Power Plant at power.  The Group 
Operating Supervisor (GOS) and the Group Shift Supervisor (GSS) were the 
licensed senior reactor operators present in the control room.  During this 
operational period, the GSS left the control room, leaving the GOS as the 
only SRO present.  While the GSS was absent, the GOS left the control room 
without realizing that he had been the only SRO present.  Both the GSS and 
the GOS returned when informed that there were no SROs present in the 
control room.


                                                            IN 91-24 
                                                            March 26, 1991 
                                                            Page 2 of 2 


At PSU, the licensee's management learned of this event through the reported 
observation by another staff member.  When the licensed reactor operator was 
interviewed by the facility director, the operator stated he did not know 
that leaving the control room unattended (with the reactor unsecured) was a 
violation of the reactor facility's technical specifications.  To prevent 
reoccurrence, the licensee has implemented a training procedure explaining 
this event and the importance of adhering to the technical specifications.  

At the Oyster Creek Nuclear Power Plant, the licensee stated that the reason 
an SRO was not present in the control room at all times was because the GOS 
had failed to follow the guidance on shift turnovers in the administrative 
procedures.  This guidance was prepared as a result of a similar event that 
occurred at Oyster Creek on October 5, 1989.  The GOS involved in this event 
had been in training for his SRO license when the October 1989 event 
occurred and had not been made aware of the subsequent guidance on the 
control room staffing requirements.  

Facility licensees are expected to be familiar with the minimum staffing 
levels for reactor operation specified in the technical specifications for 
their respective nuclear facilities or as stated in Section 50.54 (k) and 
(m) of Title 10 of the Code of Federal Regulations, as appropriate.  These 
requirements apply to non-power and power nuclear reactor facilities.

This information notice requires no specific action or written response.  If 
you have any questions about the information in this notice, please call the 
technical contact listed below or the appropriate NRR project manager.

                                  Charles E. Rossi, Director
                                  Division of Operational Events Assessment
                                  Office of Nuclear Reactor Regulation

Technical Contact:  John Thompson, NRR
                    (301) 492-1171

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